Vacuum polishing lathe



` April 3,1945.

H. E. cRozlER 2,372,812

vAcuuu romsnme mmm' Filed Nov. 24, 1944 INVENTOR. 3% we 5 6902/5@ lex/ I www Patented Apr. 3, 1945 t asiatical l ,y

. vacnnlvlrousmnoilis'nns 1o claims: (615515-235) Myf irivefntion relates to avacuum-polishing lathe and has for its principal objecuto: provide simple, convenient andfhighlpeiective meansifor accomplishing.. thef rapid and economic polishing of small structural' parts of. various shapes and sizesrand which. partswhilebeing polished; are held by vaouumon anadaptor or flxtureandthe latter'being.- carried on.x the'endiof af. shaft capaloiev of being driven at high speeds; l

A` tui-,ther objecty of invention.A is,. to a polishing lathe of the character' referrerhtot` having a simple:A and effective vacuum pump .for f exhausting? the: air from thev adaptor `ou: xtin'e which. receives the work. to be* polishedifwhich pump includes? a rotor mounted1 on: the high' speed: shaft, with. ai seriesof radiali vamesrca-miedibnsaid rotor and thelatter and-said vanos; being eccen.h trically arranged'. within the: pnn'ispschamber;

A. further object ot myfinvention is, to; provide simple andieihcient means'for corntnollingl the-:opm era-tionof. the high speedfshafftwhich carriesithe work receiving iixture and drives the vacuum Dump. 1.

With the foregoing` and other objectsiimview, my invention consistswin certaim novell features of; construction, and; arrangement offfparts which will. be hereinafter. more fully,A described. andA claimed and. illustrated in the accompanying drawing, in which:

Fig. 1 is a side elevational view of-A mw vacuum.

polishing` lathe with theendportionsthereof; in vertical section.` l

Fig. 2 is. a. detail section. taken ontheline 2,;-2 of Fig. 1'.

Fig. 3` is an elevationalview partlyin .sectioni and' showingv an. electric switch operating, means.

Fig. 4v isa plan View. of. the switch. operating device.

Fig. 5 is a perspective Viewv of the switch operating,device.

Fig. 6l is an enlarged. cross. section.. taken, on thev line 6-5 of Fig. l.

Fig. '7 is a perspective View of a modified form of the vanesusedinthevacuum pump.

Referring by numerals to the accompanying drawing, which illustrates apreferred embodiment of my invention, I0 designates a housing through which passes a shaft I I, carrying an armature I2 and the latter operating within a conventional eld I3.

Shaft II operates in anti-friction bearings Il in the end portions of housing I0 and extending entirely through said shaft is an axial duct I5. Removably positioned on the forward end of shaft I I is a disc like fixture or adaptor I6, in the front a springv used. in

face-.ofzwhiclr isaseated a1 rubber ringl Irl', against' whi'chithe zpiece-suchzasspg which isltorbe polished;

isrpositi'on ed.

' i Amasr'tight j oint'rislformedbetweonxthe ring andi the piece positionedi againstv same and thus said piece isrml'yr lield against 'said' ring, byfv the partial vacuum produced in duct` I5, and in the chamber between discrlhandA thev work, as'` will be hereinafter more fullyd described.' Suitably'securedtoshaft IIIa-diacent disc I5 is a col"- lan Hhprovided'l on its innen end witha flange I9, andi loose-1y mountedfon: said collar is a` brake ring 20, Carrying a facingai. of friction` producing material'which. is adaptedtorcontacti flange ISl Thefouter facetofc 2 lt'is-positionedfadjacent theznnen face oi` al. ringf 27., which is securedy to the end; ofmotor'housing Ill and formed in the inner face. of said' ring- 22` is afplurality, prefer`m ably three, inclined cam surfaces 23, against whichbean balls 2.1i,.l'oosely` arrangedin recesses Zfin-.the cuter: face of brak@ ringvz.

A leyerhandie: 2.&seated;in.brake ring 20; proiectsradiallyouinrardthrough a. slot 2I in housing Illy and when' saidi handleis moved: rearwardly; thel brake;Y ringvis partially' rotated. so` asgto cause-,balls 2l8ftoride uprthe'carns12 and thereby shiftvring 21V inwardlysothat iacing 2 Iy frictionally engages ange-'Iitherekiy exerting braking eiort onshaft I I,tendingtozcausesamefto cease rotating.

motor. housing, below: hand leverk 23 contains the switcl'nwhichv controls` the line conductors to and from the motor and said switch ,being actuatedby asconventional. toggle I arm 2-1.

Seatedintbrake ring; 2l! and projecting through aslot 23 iii/,housingfIILisashort arm-38 and connecting same with; toggle armi 2'Iy is a spring 3l', one or moreintermediate coils 32r (see Eig. 5).V l

When hand leverisfpositioned sothat balls .24. are at the lower ends of cams 23, the brake is released and arm 33 is positioned so that, through spring 3| switch arm 21 is in switch opening position, and thus, when said lever is moved so as to apply the brake, the switch arm will be snapped into position to open the switch in box 28, thereby `cutting off the current supply to the motor (see Figs. 3 and 4). Formed integral With or fixed to the opposite end of housing I0 is a circular wall 33, providing a pump chamber 34, which is eccentric with respect to the axis of shaft II. 'I'he outer end of this chamber is closed by a removable plate 35 and formed onthe external faces of said wall and plate are heat disseminating fins 33 and 35a respectively.

The reduced end Ila of shaft Il projects eccentrically into chamber 34 and concentrically mounted thereon is the cylindrical body of a pump rotor 36, provided with a plurality of radially disposed slots 31, within which are arranged for sliding movement, vanes 38, the bottom edges of which, when the pump is in operation, bear on the inner face of wall 33. The bottom faces of the slots 31 are curved lengthwise and thebottom faces of vanes 38 are correspondingly curved. Formed in the rear faces, in the direc tion of rotation of the pump rotor, are ducts 39,`A which extend from the bottoms of said vanes t points near the top faces thereof.

If desired, the ducts just described may take,

the form of holes such as 40 drilled in ther vanes (see Fig. 7). The curved bottoms of the slots 31 are connected by short ducts 4I, with circumferential grooves 42 in the periphery of the reduced end of shaft Il on which therotor 36 is mounted and apertures 43 are formed in the shaft between said grooves 42 and the axial duct i5.

Formed through the end wall of the motorl housing and establishing communication between the compression side of chamber 34 and the interior of the motor housing are ports 44 which deliver jets of air compressed in the pump chamber, directly against and over the armaturev of the motor thus cooling same.

In operation, the actuation of hand lever 26, to move balls to the lower ends of cams 23, releases brake 20, 2l and at the same time arm 3l) through spring 3| shifts switch lever into position so as to close the circuit to the motor and thereby start same.

The operation of rotor 36 and vanes 38 acts to exhaust air through duct I in the motor shaftV which air after being compressed in chamber 34, discharges through ports 44 and passes over the' armature with cooling effect. When an article to be polished is placed against ring I1, the partial vacuum in the chamber between disc I6 and said article, will by suction anchor the latter to the adapter so that said article is rotated at motor speed during the polishing operation.

Reverse movement of lever 22, sets the brake against flange 22 and at the same time, switch lever 21 is actuated to open the motor circuit.

Thus it will be seen that I have provided a vacuum polishing lathe which is simple in structure, inexpensive of manufacture and very effective in performing the functions for which it is intended.

It will be understood that minor changes in the size, form and construction of the various parts of my improved vacuum polishing lathe may be made and substituted for those herein shown and described without departing from the spirit of the invention, the scope of which isset forth in the appended claims.

claim 1 and with manually operable means for. controlling the operation of said motor driven Shaft- 3; In a vacuum polishing lathe, a shaft having a longitudinal duct, means for rotating said shaft,

a work supporting fixture on the end of said shaft'and la continuous flexible flange on said fixture. x

4. A vacuum polishing lathe as set forth in claim 3, With means actuated by said shaft for exhausting` air through the duct in said shaft and from the space between said fixture and the piece applied to said flexible flange.

5. A vacuum polishing lathe as set forth in claim 3, with means actuated by said shaft for exhausting the air through the duct in said shaft and from the space between said fixture and the piece applied to said flexible flange and manually operable means for controlling the operation of said shaft.

6 In a vacuum polishing lathe, an electric motor, the shaft of which is provided with a longitudinal duct, a work receiving fixture carried by one end of said shaft, the suction side of which pump has communication with the duct in said shaft and a manually operable brake for controlling the operation of said shaft.

7. A vacuum'polishing lathe as set forth in claim 6 with a switch for controlling flow of current to said motor and operating connections between said brake and said switch' whereby current flow to the motor is cut oil' when the brake is' applied 'and current flow to the motor established when the brake is released.4

1 8.Y A vacuum polishing lathe as set forth in claim 6, and with means for directing jets of air from the compression side of said vacuum pump toward and against the armature of said electric motor.

9. In a. vacuum polishing lathe the combination with a driven shaft .havinga longitudinal duct, of a work receiving fixture on one end of said shaft, a continuous elastic seat on said flxture for an article to be polished, the chamber between said xture and the piece applied to said flange having communication with the duct in said shaft and means for establishing a partial vacuum in said duct and space.

10. The combination as set forth in claim 9 and with manually operable means for controlling the operation of said shaft.

HAROLD E. CROZIER. 

